Patent application number | Description | Published |
20090055085 | VARIABLE VALVE TIMING APPARATUS AND CONTROL METHOD THEREOF - At the time of reference position learning, an operation amount of an actuator is set such that intake valve phase changes to a position of most retarded angle in a region where the amount of change in intake valve phase relative to the actuator operation amount is small (S | 02-26-2009 |
20090071425 | VARIABLE VALVE TIMING APPARATUS - In a variable valve timing apparatus having a VVT mechanism in each of a plurality of banks, start of a valve timing control is not permitted until reference position learning of valve timing is completed in the corresponding bank and in other banks. Accordingly, the plurality of banks come to have matching valve timing setting at the time of valve timing control, whereby variation in the amount of air introduced to cylinders can be suppressed, and satisfactory combustion characteristics can be maintained. | 03-19-2009 |
20090101094 | VARIABLE VALVE TIMING SYSTEM - An ECU transmits a pulsed operation command signal, indicating operation commands for an electric motor used as a VVT actuator, to an electric-motor EDU. The electric-motor EDU recognizes the combination of the direction in which the actuator should be operated (actuator operation direction) and the control mode based on the duty ratio of the operation command signal, and the rotational speed command value based on the frequency of the operation command signal. The electric-motor EDU controls the electric motor according to the control commands. The duty ratio indicating the combination is set such that even if the duty ratio is falsely recognized, a false recognition concerning the actuator operation direction is prevented, such false recognition causing the valve phase to change in an undesirable direction, and even if the actuator operation direction is falsely recognized, the rate of change in the phase is restricted. | 04-23-2009 |
20090101095 | VARIABLE VALVE TIMING SYSTEM AND METHOD FOR CONTROLLING THE SAME - In an intake valve phase control after an engine stop command is issued, a stop-time phase is used as a target value. In the intake valve phase control, when the mode changeover condition is not satisfied, and an electric motor that serves as an actuator is not in a locked-state, the highest-speed mode, in which the amount of electric power supplied to the electric motor is fixed to the maximum value, is selected to reliably change the intake valve phase by a required amount. Then, the intake valve phase comes close to the stop-time phase and the mode changeover condition is satisfied, the control mode is changed from the highest-speed mode to the normal mode to set the control phase to the stop-time phase with higher accuracy, and the feedback control over the intake valve phase is executed. | 04-23-2009 |
20090194047 | VARIABLE VALVE TIMING APPARATUS AND CONTROL METHOD THEREFOR - An ECU executes a program including the steps of: controlling, when the phase of an intake valve is a phase advanced relative to a threshold value CA (FF) (NO in S | 08-06-2009 |
20090255510 | VARIABLE VALVE TIMING APPARATUS AND METHOD OF DETECTING VALVE PHASE THEREOF - When the engine speed is high (determination of YES at S | 10-15-2009 |
20100012061 | VARIABLE VALVE TIMING SYSTEM - A valve timing control is executed by an ECU that controls an engine and an electric-motor ECU that controls an electric motor. The ECU and the electric-motor EDU serve different functions. The ECU sets the target phase of an intake valve based on the engine operating state, and prepares a rotational speed command value for the electric motor that serves as an actuator such that a phase feedback control loop, in which the intake valve phase is caused to match the target phase, is formed. The electric-motor EDU forms a feedback control loop for the motor speed, in which the electric power supplied to the electric motor is controlled such that the electric motor rotates in accordance with the rotational speed command value. | 01-21-2010 |
20100126451 | DEVICE AND METHOD FOR CONTROLLING INTERNAL COMBUSTION ENGINE - If it is necessary to rapidly change a phase of an intake camshaft and an intake VVT mechanism relatively slow in responsiveness as it is associated with an “A” bank of a V-type, 8-cylinder engine is in operation for at least a predetermined period of time, an ECU executes a program including the step of controlling intake VVT mechanisms to operate those associated with both the “A” bank and a “B” bank. | 05-27-2010 |
20100222990 | VARIABLE VALVE TIMING APPARATUS AND CONTROL METHOD THEREFOR - An ECU executes a program including the step of stopping power supply to an electric motor if a phase of an intake valve is in a first region between the most retarded angle and CA. In the case where the phase of the intake valve is in the first region, the rotational speed of relative rotation between the output shaft of the electric motor and a sprocket is reduced at reduction gear ratio R thereby to vary the phase of the intake valve. In the case where the phase of the intake valve is in a second region between CA and the most advanced angle, the rotational speed of the relative rotation is reduced at reduction gear ratio R thereby to vary the phase of the intake valve. | 09-02-2010 |